luckadjusted
NFL Week 9 · 2026

Week 1 2025 · September 7, 2025

49ers at Seahawks, Week 1 2025: who deserved to win?

The 49ers beat the Seahawks 17–13, but the replays call it close to a coin flip: with the way both teams played, the 49ers win 5 of 10. Luck ran their way: fumble bounces alone were worth 41 points of win probability to the 49ers.

Before kickoff the 49ers were 57% favorites. The game turned on a luck play (Q4, 0:42 left): the Seahawks fumbled and the 49ers recovered, worth 22 points of win probability to the 49ers.

Final

San Francisco 49ers 17
Seattle Seahawks 13

September 7, 2025 · Lumen Field · Closing line: 49ers −2.5

Luck index +47 49ers lucky · −47 Seahawks

Each team’s own plays from this game, resampled into new drives 4,000 times: with the way both teams actually played, how often does this performance win? How the replay works

Ten replays. 49ers win 5, Seahawks win 5.

  1. 1 SF 47 SEA 24
  2. 2 SF 34 SEA 21
  3. 3 SF 15 SEA 6
  4. 4 SF 33 SEA 27
  5. 5 SF 24 SEA 22
  6. 6 SF 27 SEA 30
  7. 7 SF 13 SEA 18
  8. 8 SF 17 SEA 24
  9. 9 SF 7 SEA 20
  10. 10 SF 17 SEA 37

Three other ways to ask

Each answers a different question, so none of them replaces the replay above.

The closing betting line, turned into a probability. What everyone knew before the game.

The line plus what this game showed, weighted by how much one game can tell. It stays close to the line because one game says little.

Every kick, fumble bounce, drop, conversion and judgment call redrawn; everything else fixed. The narrowest view of luck.

How 4,000 replays ended

49ers win 53% of them, Seahawks 47%, counting the 6% still level after regulation as half each. The line is what actually happened: 49ers by 4.

Show as a table
Final margin in the replaysShare of replays
49ers by 17+11.4%
49ers by 9–1615.6%
49ers by 1–821.6%
Level after regulation5.7%
Seahawks by 1–822.1%
Seahawks by 9–1613.5%
Seahawks by 17+10.0%

Where the luck was

What the luck was worth

Every lucky and unlucky play, weighted by the moment it happened: its swing in win probability, added up by kind. A missed kick in a decided game counts for nothing; the same kick at the end of a tie game can be most of a win.

Swings add up across a game, so in one that went back and forth they can pass 100%. On the scoreboard the same luck was worth +1.0 points to the 49ers: the final margin was 49ers by 4, without the luck 49ers by 3. Luck shares are the fitted ones (how much of each kind is luck).

The kicks

How likely each kicker was to make that kick (his own record, the distance and the weather), and what happened.

  • J. Moody, 27 yds missed · 96% expected
  • J. Myers, 48 yds made · 76% expected
  • J. Moody, 36 yds blocked · 91% expected
  • J. Moody, 32 yds made · 93% expected
  • J. Myers, 37 yds made · 92% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: 49ers 9 for 61 yards, Seahawks 4 for 30 yards

Every accepted flag, in order, and what it did to the helped team’s chance of winning at that moment, including any play it wiped out (points on the scoreboard in grey). A flag in a decided game is worth nothing; one at the turn of a close game can be worth most of a win. Judgment calls count half toward luck; pre-snap fouls, which repeat, don’t count. How calls are valued

WhenFlagWin probability for
Q1 12:19 Delay of Game on the Seahawks, 5 yards · pre-snap 0% SF +0.4 pts
Q1 12:14 Offensive Holding on the 49ers (Ji'Ayir Brown), 5 yards +1% SEA +0.5 pts
Q1 6:47 Roughing the Passer on the Seahawks (Leonard Williams), 15 yards +8% SF +2.2 pts
Q1 5:23 False Start on the 49ers (Luke Farrell), 5 yards · pre-snap +1% SEA +0.5 pts
Q1 3:00 Unnecessary Roughness on the 49ers (Deommodore Lenoir), 15 yards +3% SEA +1.8 pts
Q2 13:46 Defensive Pass Interference on the 49ers (Upton Stout), 3 yards +10% SEA +3.5 pts
Q2 12:15 Player Out of Bounds on Kick on the 49ers (Siran Neal), 5 yards +1% SEA +0.3 pts
Q3 15:00 Illegal Use of Hands on the Seahawks (Eric Saubert), 5 yards +2% SF +0.4 pts
Q4 14:50 Illegal Contact on the Seahawks (Julian Love), 5 yards +1% SF +0.3 pts
Q4 9:52 False Start on the 49ers, 5 yards · pre-snap +4% SEA +0.6 pts
Q4 7:32 Offensive Holding on the 49ers, 10 yards +9% SEA +1.8 pts
Q4 1:06 Defensive Offside on the 49ers (Bryce Huff), 5 yards · pre-snap +7% SEA +0.5 pts
Q4 0:42 Unsportsmanlike Conduct on the 49ers (Deommodore Lenoir), 8 yards +6% SEA +0.7 pts

49ers penalties, every game · Seahawks penalties, every game · All teams, 2025

When it happened

Seahawks’ chance of winning

As low as 0% and as high as 76%. Numbers mark the biggest luck moments, listed below.

nflfastR’s in-game win probability. It ignores the betting line, so it starts near even. Shaded above the middle while the Seahawks were ahead in it, below while the 49ers were.
#WhenWhat happenedWin probability forNext drive
1 Q2 13:46 Defensive Pass Interference on the 49ers (Upton Stout), 3 yardsJudgment calls · no snap history yet +10% SEA SEA: Touchdown
2 Q3 4:33 The 49ers converted 4th & 23rd & 4th downs · 63% expected +9% SF SF: Missed field goal
3 Q3 2:21 J. Moody had a 36-yard field goal blockedKicks · 91% expected for him +19% SEA SF: Field goal
4 Q4 11:18 The 49ers converted 4th & 23rd & 4th downs · 63% expected +9% SF SF: Field goal
5 Q4 9:52 The 49ers were stopped on 3rd & 143rd & 4th downs · 24% expectedFalse Start on the 49ers, 5 yardsPre-snap flags +10% SEA SF: Field goal
6 Q4 7:32 Offensive Holding on the 49ers, 10 yardsJudgment calls +9% SEA SEA: Field goal
7 Q4 1:44 The 49ers converted 3rd & 33rd & 4th downs · 45% expectedThe 49ers got away with an interception-worthy throwInterceptions · defenses catch 54% of interception-worthy throws +19% SF SF: Touchdown
8 Q4 0:42 The game turned hereThe Seahawks fumbled and the 49ers recoveredFumble bounces · loose balls are close to 50/50Unsportsmanlike Conduct on the 49ers (Deommodore Lenoir), 8 yardsJudgment calls · 16 flags in 3864 snaps before, position avg 1 per 244 +22% SF –

Missing players

Key players (usually on the field for half the snaps or more) who missed this game or part of it, valued by position and quality. The same players are missing in every replay, so this counts as luck in points only.

  • Uchenna Nwosu (SEA LB), out · 0.2 pts
  • Malik Mustapha (SF FS), out (IR) · 0.4 pts

Adjust the assumptions

Disagree with how much of a fumble bounce or a pass interference call is luck? Change it and the coin-flip replay reruns in your browser.

Only coin-flips re-rolled

49ers 68% · Seahawks 32%

Final margin
49ers by 4
Luck in points
1.0 for the 49ers
Luck-adjusted margin
49ers by 3.0
Replay with same day's form
49ers 53% · Seahawks 47% unchanged: why
How much of each is luck?

0% treats it as skill, 100% as pure luck. The tick is our fit.

What counts

None by default: our tests measured no carryover after a lucky break. Slide it up to count a break for more than its own swing. Why

Flip a play

Force the other outcome, in this game and in every replay: a made kick becomes a miss, a stop becomes a conversion, a flag goes the other way.

About these numbers

Play-by-play and win probability from nflfastR via nflverse; kicks valued against each kicker’s own record; drops and interception-worthy throws from FTN charting; injuries from snap counts and injury reports.

Methodology and validation · All Week 1 2025 games · 49ers · Seahawks

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